Never been to the Biergarten although I should. I've known one of the owners for about 10 years now. Mahars has some good beers. My personal favorite is the pump station because why? They have GREAT BEER!
I don't know if I can pick just one. Mahar's, Wolff's Biergarten, Pump Station, Brown's Brewing... all are very good. Just depends on what you're looking to drink and what you want to do while drinking.
It's been a while since I have gone drinking in Albany but I agree the pump station was good. And if you just want to watch the game and have fun I went to Andy's by the hospital with a bunch of co-workers all the times.